The present invention relates to ovens, and more particularly, to improvements in vertical conveyorized ovens to allow more effective heating and operation.
Commercial ovens are available to perform a variety of broiling, baking or toasting functions. Given the commercial setting, such ovens are designed to perform those functions in a manner to efficiently satisfy volume requirements, on a predictably repeatable basis. Preferably the quality of the products produced in those ovens can be controlled and maintained at desired standards independent of the particular operating personnel, whose operating habits may vary significantly even for a given establishment. Additionally, the commercial oven is preferably constructed so as to facilitate internal and external cleaning to insure healthfulness of the products cooked in the oven and satisfaction of applicable health and safety codes. A further consideration relates to the space and bulk requirements of the oven. Preferably the oven should be easily transportable and require as little space as possible, while satisfying production requirements.
Conveyorized ovens generally offer a more regulated approach to cooking. Products are ideally placed on a conveyor at a given point, and are transported through the conveyor at a predetermined speed, to a predetermined unloading point. Most such conveyors are horizontally oriented and are therefore bulky, consume significant floor space and require substantially permanent installation. They are therefore not usable in many restaurants, particularly where the original kitchen design did not contemplate inclusion of such a horizontal conveyorized oven.
Another, somewhat less apparent problem, associated with such horizontal conveyor systems relates to variations in operating procedures and resulting product specifications. Those familiar with such ovens recognize that operators, particularly when pressured by a rush of business, frequently load products closer to or beyond the oven entrance, and remove products closer to or before the oven exit. As a consequence, baking cycles and the product specifications tend to vary even for a given oven with constant operating control settings. Horizontal conveyorized ovens also require significant effort in order to clean and maintain. Accordingly, while such horizontal conveyorized ovens are capable of performing production cooking functions, they suffer significant limitations.
Spiral-type cooking ovens advantageously require less floor space than horizontal conveyors ovens. However, as with horizontal conveyor ovens, production capacity is limited by end to end sizing of the products. Uniformity of heat flow through the spiral oven is typically another concern. Moreover, many such spiral-type ovens incorporate support and drive structures within the central heating area of the oven. That construction may cause maintenance problems and render necessary cleaning and maintenance more difficult.
As with spiral-type ovens, vertical conveyorized ovens require less floor space than horizontal ovens. However, in vertical ovens production space is not limited by end-to-end sizing of the product. Thus, given that the thickness of products, such as pizzas, is relatively small, more products may be simultaneously cooked within a small vertical oven than in a far larger horizontal conveyorized oven.
One such vertical conveyorized oven is described in U.S. Pat. No. 5,030,809 to Buday for vertical oven. The vertical oven described in that patent describes a production heating system that can efficiently bake a significant number of products, and yet be easy to clean and maintain. While the vertical oven disclosed in U.S. Pat. No. 5,030,809 provides significant advantages over prior conveyorized ovens, the need for further improvements has been recognized in order to improve the air flow within the oven and insure uniformity of bake and appearance of the finished product. As described below the present invention provides such improvements to facilitate the heated air flow within a vertical conveyorized oven. Additional improvements described herein also relate to the construction of pan trays which serve as both baking pans and oven transport trays, engageable with the vertical conveyor assembly to transport the products through the vertical oven. The present invention further provides for simultaneous regulation of the heated air circulation and conveyor speed in order to obtain optimum product specifications.